Back seat for motor cycles



Nov. 1s, 1924. 1,516,176

H. A. DRn-:s'Sx-:N

BACKSEAT FOR MOTOR CYCLES Filed om. '26, 1929- 2 sheets-Sheet 1 NOV. 18, 1924- v' v 1,516,176

I H. A. DRlEssEN BACKSEAT FOR MOTOR CYCLES Filed oct. 26, w22k .2 shuts-sheer 2 Fig- E- Patented Nov. 18, 1924.

UNITED STATES hldi HERMANUS ANTONIUS DRIESSEN, OF THE HAGUE, NETHERLANDS.

BACK SEAT FOR MOTOR CYCLES.

Application led October 26, 1922. Serial No. 597,187.

[o all whom t may concern Be it known that I, HERMANUS ANTONIUS Dnmssnx, a citizen of the Kingdom of the Netherlands, and resident of The Hague, Netherlands` have invented a certain new and useful Back Seat for Motor Cycles, of which the following is a specification.

The invention relates to an improved additional backseat for motorcycles. Already many different kinds of'backseats have been proposed with a view to obtaining a product which meets all reasonable requirements'. One of the best, which moreover shows some resemblance to the object of this application, is specified in the published Dutch patent-application No. 17703 Ned. cl. G3 g. Such seat is of' the type, in which the rear end of' the seat proper is provided with one or more links, the under ends of which are connected to the fixed frame by means of draw-springs, while the forepart of the seat proper is rotatable around a horizontal shaft of' the frame. The lower end of each ofl the links is pivotally connected with one arm of a doublearmed lever, the other arm of which is fiexibly connected with the frame.

This particular construction has indeed many advantages, since, by the connection of the fore-part the seat is prevented from moving laterally, a sufiicient space is obtained for permitting the seat proper to spring as necessary, and, still it can, be mounted but a short distance above the muclguard, so that the stability is not greatly decreased. 'However the springing itself does notmeet all reasonable requirements,

' because the tension is decreased by the holding of the springs which act directly on the link. Moreover, there is not enough attention paid to the requirement, that the upward force of the springs must be very -slight -at the beginning of the downward movement ofv the seat, and mustl increase rapidly on further downward movement.

It is the purpose of the present invention to improve the said spring arrangement,

ff and-therefore itis characterized by the fact,

that the spring effect is obtained solely by means of draw-springs, which act Von links by the intermediary ot' levers, while the arms, on which the springs act, will, in the first part of the downward movement of the seat form an ang-le of nearly 1800 with the direction in which the springs act. Thus it is obtained, that the springs first act with but slight force on the scat, while the force on further downward movement, increases strongly with the decrement of the said angle.

lVith the construction which is most evident, the said obtuse angle4 wouldcause the springs to be located very low, so that they would be in the way for the passenger', if no particular guard be applied thereto. For overcoming this slight objection, and at the same time for obtaining a very practical and simple construction, the levers may be formed according to the present invention, as bell-crank-levers, the arms of which are at an angle of about 90 to each other. The arms, on which the springs act, are directed forwards and upwards, so that the fulcrums of the springs can be situated near the horizontal pivot axle of the seat proper.

As one example, in the accompanying drawings, an embodiment is shown 'for carrying the invention into effect, wherein` 1 is an elevation of' the improved seat,

Fig. 2 is a perspective elevational view,

3 is a rear view of a clip for maintaining the seat-bottom, when desired, in a nearly horizontal position, in cooperation with a belt with a hook,

Figs. 4 and 5 are longitudinal sections of the said clip with the belt in two different positions, and

Fig. 6 is an elevation showing the arf rangement of the connecting device.

Fig. 7 is ay fragmentary view showing the adjustable spring connecting means.

The seat-bottom l, supporting a cushion 2, is pivotally connected by a ball-bearing 3, to the middle ofa. fixed horizontal shaft at, which is supported by two rods 5', in order to prevent lateral movements. These rods 5 are supported on rods 5 which bear in any desired manner, upon a stationary part such as the rear axle of' the cycle, by .means of apertures 6. A second connection is applied between rods 5 and any part of' the machine fra-me proper, by means of a flexible strap 7, to be wrapped about any `c onvenient part of the fra-me, to hold rods 5 in set position. The rear end of the seat- CII bottom is provided with two links 8, the under ends of which are pivotally connected to the` arms orp two bell-crank-levers 9, which are fulcrumed on a horizontal spindle 10, supported by a trame 11, 12, which is connected to the rods rlhe other arms oit the bell-crank-levers are pivotally connected to spring bearers 1,3. Between these bearers 13 and other bearers 15 (see Fig. 7) are positioned coiled springs 1st. The bearers 13 and 15 are formed ot two parallel spaced plates, connected by cross bolts 13, and 15. The bearers 15 are rotatably mounted on short shafts 18, which are situated beneath, and adjacent to, the shat't el, the shafts 18 being adjustably mounted on trame members 12, by means ot screw threaded eye bolts 19 and nuts 20, so that the tension ot the springs 14, can be varied at will by adjusting the position ot bearers 15. In ranging the springs lil in the above described manner, at the inner sides ot the rods 12, they otter no obstruction to the passenger, and all damage to his legs or his clothes, is avoided.

In Fig. 1 the extreme low position ot the seat-bottom 1 is indicated by dotted lines, so that it is clearly to be seen, that there is a considerable distance between this position and the normal position. Hence, a. Yfree springing action is secured, without any ne cessity to mount the seat-bottom at a relatively great distance above the mud guard 16. t clearly appears from Fig. 1, that tho springs 1s, at the lirst part of the downward movement of the seat-bottom, act with only a very small torce. while this t'orce increases rapidly on any further downward moyement, on acount ot the aforementioned angle decreasing toward 900.

A belt or the like 17, ot any desired matcrial and fastened in any appropriate manner, may be provided for maintaining the seatbottom in a nearly horizontal position when l not used. By the particular construction ot a back seat according to the present invention, the springs have only Very slight` tension, when the rear end of the seat-bottom is in its highest position. Therefore, it is very necessary that there be a device, by which the seat-bottom can be maintained in a somewhat lowered position. In order that this may always be easily obtained, and without placing the vehicle on its support, there may be provided a clip 21 as indicated in Fig. 3 and a single belt 24 as indicated in Figs. l, 5 and t3. The belt 24E is connected to the frame 11, and passes through the clip 21. This belt has a hook z3, attached to its underside. Then the belt is drawn backwards, and at the same time pressing down the seat proper, the hook 23 can be placed over the rear end of the clip, as indicated in Fig. t, whereby the seat-bottom is maintained in a nearly horizontal position.

Ytherwise, the hook 23 will rest against a. bridge member 22, so that the seat-bottom can spring freely.

.ln F 6 the arrangement ot the locking device 21 24, is clearly shown.

laying fully described my invention, what l vclaim is:

1. it back seat t'or motorcycles, comprising, a iframe detachably connectable to a motorcycle, a horizontal shaft on the traine, a seat rotatably connected to the shaft at its liront portion, bell-crank-levers pivoted to the trame, links connected at one end to the rear portion otI the seat, and at the other end to arms ot the bell-crank-levers, spring supports on the trame, tension coil springs conneeting the spring supports and the tree arms ot the bell-crank-levers, whereby the springs tend to force the seat upwardly, the angles between the springs and the arms ot the bell cranks to which the springs are conneeted, being substantially of 180C when the seat sustains merely its own dead weight.

2. A backseat according toclaim 1, the bell-cranklever being at an angle ot about 900, the arms to which the springs are attached being directed forwardly and upwardly, the spring supports being situated near and beneath the said horizontal shaft.

3. A backseat according to claim 1, including a belt for preventing the seat when not in use 'trom heilig spring actuated to its uppermost position.

fr backseat according to claim 1, the bell-cranlclever being at an angle ot about U00, the arms to which the springs are attached being' directed forwardly and upwardly, the spring supports beine' situated near and beneath the said horizontal shaft, includinga belt for preventing the seat when not in use from being spring actuated to its uppermost position.

5. A backseat according to claim 1, including a belt for preventing theseat when not in use trom being spring actuated to its uppermost position, a clip on the seat to accommodate the said belt and a hook on the belt cooperating` with the clip, whereby the seat may be Jfree, or else maintained in a somewhat sagged position.

6. A backseat according to claim 1, the bell-crank-lever being at an angle of about 900, the arms to whichthe springs are attached being directed forwardly and upwardly, the spring supports being situated near and beneath the vsaid horizontal shaft, including a belt for preventing the seat when not in use troni being spring actuated to its uppermostposition, a clip on the seat to accon'imodatc the said belt and a hook on the belt cooperating with the clip, whereby the seat may be tree, or else maintained in a somewhat sagged position.

7. A backseat according to claim 1, including a belt for preventing the seat when not in use from being spring actuated to its uppermost position, a clip on the seat to accommodate the said belt and a hook on the belt cooperating with the clip, whereby the seat may be free, or else maintained in a somewhat sagged position, said clip including means to hold the hook when the seat bottom is free.

8. A backseat according to claim 1, the bell-crank-lever being at an angle of about 90", the arms to which the springs are attached being directed forwardly and upwardly, the spring supports being situated near and beneath the said horizontal shaft, including a belt for preventing the seat when not in use from being spring actuated to its uppermost position, a clip on the seat to accommodate the said belt and a hook on the belt cooperating with the clip, whereby the seat may be free, or else maintained in a somewhat sagged position, said clip including means to hold the hook when the seat bottom is free.

9. A backseat according to claim 1, said springs being adjustably supported on said frame.

10. A backseat according to claim 1, the bell-crank-lcver being at an angle of about 900, the arms to which the springs are attached boing directed forwardly and up wardly, the spring supports being situated near and beneath the said horizontal shaft, said springs being adjustably supported on said frame.

11. A backseat according to claim 1, including a belt for preventing the seat when not in use from being spring actuated to its uppermost position, said springs being adjustably supported on said frame.

12. A backseat according to claim 1, the bell-crank-lever being at an angle of about 90, the arms to which the springs are attached being directed forwardly and upwardly, the spring supports being situated near and beneath the said horizontal shaft, including a belt for preventing the seat when not in use from being spring actuated to its uppermost position, said springs being adjustably supported on said frame.

13. A backseat according to claim 1, in cluding a belt for preventing the seat when not in use from being spring actuated to its uppermost position, a clip on the seat to accommodate the said belt and a hook on the belt cooperating with the clip, whereby the seat may be free, or else maintained in a somewhat sagged position, lsaid springs being adjustably supported on said frame.

111. A backseat according to claim 1, the bell-crank-lever being at an angle of about 900, the arms to which the springs are attached being directed forwardly and upwardly, the spring supports being situated near and beneath the said horizontal shaft, including a belt for preventing the seat when not in use from being spring actuated to its uppermost position, a clip on the seat to accommodate the said belt and a hook on the belt cooperating with the clip, whereby the seat may be free, or else maintained in a somewhat sagged position, said springs being adjustably supported on said frame.

15. A backseat according to claim 1, including a belt for preventing the seat when not in use from being spring actuated to its uppermost position, a clip on the seat to accommodate the said belt and a hook on the belt cooperating with the clip, whereby the seat may be free, or else maintained in a somewhat sagged position, said clip including means to hold the hook when the seat bottom is frec,said springs being adjustably supported on said frame.

- 16. A backseat according to claim 1, the bell-crank-lever being at an angle of about 90, the arms to which the springs are attached being directed forwardly and upwardly, the spring supports being situated near and beneath the said horizontal shaft, including a belt for preventing the seat when not in use from being spring actuated to its uppermost position, a clip on the seat to accommodate the said belt and a hook on the belt cooperating with the clip, whereby the seat may be free, or else maintained in a somewhat sagged position, said clip including means to hold the hook when the seat bottom is free, said springs being adjustably supported on said frame.

In testimony whereof, I have signed my name to this specification.

HERMANUS ANTONUS DRESSEN. 

